UNIVERSITY   OF  CALIFORNIA 

COLLEGE    OF    AGRICULTURE 
AGRICULTURAL   EXPERIMENT  STATION 

CIRCULAR  No.  257 
February,  1923 

THE  SMALL-SEEDED  HORSE   BEAN 

Vicia  fab  a  var.  minor 
P.  B.  KENNEDY 


A  valuable  small-seeded  uniform  horse  bean  for  cover  crop  purposes. 

INTRODUCTION 

The  purpose  of  this  circular  is  to  introduce  to  the  farmers  of 
California  the  small-seeded  horse  bean  as  a  valuable  winter  green 
manure  crop,  and  to  a  less  extent  as  a  hay,  silage  and  grain  ration 
crop  for  stock. 

That  there  is  need  of  a  legume  for  green  manuring  purposes  that 
will  grow  more  satisfactorily  during  the  cool  winter  weather  than  the 
bitter  clover,  Melilotus  indica,  and  the  vetches,  is  well  known.  The 
horse  bean  has  been  found  satisfactory  as  a  winter  grower  and  the 
only  objection  to  it  has  been  the  excessive  weight  of  seed  required 
because  of  the  large  size  of  the  type  of  bean  on  the  market.  The  follow- 
ing extracts  bear  out  this  statement. 


Z  UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 

R.  McKee  in  Farmers'  Bulletin  969,  United  States  Department  of 
Agriculture  (1918),  says:  "Various  varieties  of  horse  beans  have  been 
tested  in  the  United  States  for  green  manuring  purposes  in  compari- 
son with  other  legumes.  Very  satisfactory  results  have  been  obtained 
in  this  work  in  the  citrus  districts  of  California  and  while  the  crop 
has  not  been  used  on  an  extensive  scale  as  a  green  manure  this  has  been 
largely  due  to  the  high  cost  of  seed.  The  only  seed  available  in  com- 
mercial markets  in  the  United  States  is  that  of  the  large-seeded  varie- 
ties and  while  the  price  per  pound  is  comparatively  low,  the  quantity 
necessary  for  seeding,  on  account  of  the  large  size  of  the  seed,  makes 


^JflfeJM  HBHRfe*  ,y         lHElfc:l*» 

KflRMtafttl. 

^  ^QhHhB^^^^I 

Fig.  1. — Horse  beans  are  well  adapted  for  green  manuring  purposes  in  the 
citrus  groves  of  Orange  County.     Photo  taken  December  30,  1922. 


it  an  expensive  crop  to  plant.  The  introduction  and  use  of  small- 
seeded  varieties  would  overcome  this  difficulty,  and  it  seems  likely  that 
this  will  be  accomplished  in  the  near  future." 

G.  W.  Hendry,  in  Bulletin  294,  Agricultural  Experiment  Station, 
University  of  California  (1918),  in  referring  to  the  large-seeded  type, 
says,  "it  has  been  employed  both  as  a  green  manure  and  an  orchard 
cover  crop,  but  because  of  the  large  amount  of  seed  required  (table  9) 
is  an  expensive  crop  for  such  use. ' ' 

Table  9,  in  the  above  mentioned  publication,  gives  the  average  num- 
ber of  seeds  in  a  pound  as  275.  Of  this  large  seeded  type,  therefore, 
if  sown  at  the  rate  of  one  seed  to  a  square  foot,  158  pounds  would  be 
required  to  cover  an  acre.  At  this  rate  of  seeding  the  cost  at  four 
cents  a  pound  would  be  $6.32  an  acre.    Of  the  small-seeded  type  (see 


Circular   257]  TI1E   SMALL-SEEDED  HORSE  BEAN  3 

frontispiece),  75  pounds  of  seed  or  less  to  the  acre  would  be  required, 
so  that  the  cost  may  be  considerably  reduced.  (See  pi.  1.)  In  orchards 
much  less  seed  is  required,  depending  upon  the  space  available  for 
cover  crop  planting,  which  varies  with  the  age  and  type  of  fruit  tree. 
In  some  instances,  as  in  old  citrus  groves,  one-half  the  area  is  occupied 
by  the  trees.     (See  fig.  1.) 


HISTORY  OF  THE  HORSE  BEAN 

The  horse  bean  is  one  of  the  oldest  cultivated  plants  known,  since 
its  culture  extends  back  to  prehistoric  times.  Large  quantities  of 
seed  were  found  in  the  excavations  at  Troy.  The  origin  of  the  horse 
bean  is  obscure,  but  the  evidence  points  toward  Persia  as  its  original 
home.  The  Romans  probably  brought  it  from  Persia  and  distributed 
it  throughout  Europe.  From  Europe  it  was  brought  to  the  eastern 
United  States  by  the  colonists,  and  to  the  western  part  of  the  con- 
tinent by  the  mission  fathers.  Horse  beans  were  utilized  by  the  an- 
eients  in  a  number  of  ways.  Certain  sects  used  them  in  judicial  pro- 
ceedings. If  the  jury  cast  the  white  form  of  horse  bean  the  prisoner  was 
exonerated ;  if  the  black,  he  was  condemned.  Beans  were  also  regarded 
as  a  symbol  of  death  and  on  this  account  were  not  eaten  by  certain 
Egyptian  priests.  Because  of  their  black  spots  the  flowers  of  the 
horse  bean  were  regarded  as  an  important  decoration  at  funerals,  and 
the  beans  themselves  were  considered  an  especially  appropriate  food 
on  such  occasions.  Pythagoras,  the  ancient  philosopher,  is  said  to 
have  forbidden  his  students  to  eat  horse  beans  because  of  their  un- 
favorable dietetic  properties. 


UTILIZATION  OF  THE  HORSE  BEAN 

Numerous  small  plantings  of  horse  beans  have  been  found  through- 
out the  United  States  and  Canada,  being  made  especially  by  that  class 
of  our  population  which  comes  to  us  from  the  countries  bordering  on 
the  Mediterranean.  As  human  food  they  are  used  green  or  dry. 
The  plant  may  be  made  into  hay  or  silage,  fed  green,  or  plowed  under 
as  a  green  manure.  The  beans  are  used  as  a  substitute  for  grain  in 
rations  of  milch  cows,  and  to  some  extent  in  rations  of  other  stock. 
They  are  also  ground  up  and  form  an  ingredient  of  some  prepared 
poultry  foods.  In  some  instances  the  seed  is  roasted  and  ground  and 
combined  as  an  adulterant  with  coffee. 


4  UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 

That  the  seeds  are  very  high  in  protein  may  be  gathered  from  the 
following  analysis  given  by  Woll:1  moisture,  11.3  per  cent;  protein, 
26.6;  fat,  1.0;  fiber,  7.2;  nitrogen-free  extract,  50.1;  ash,  3.8.  Harz2 
gives  the  composition  of  both  the  large  and  small  seeded  types  on  an 
air  dry  basis  as  follows: 

Large-seeded  Small-seeded 

Per  Cent  Per  Cent 

Moisture    13.00  12.75 

Protein    24.23  25.41 

Fat    2.28  2.01 

Fiber    8.11  11.57 

Nitrogen  Free  Extract 49.74  45.43 

Ash     2.64  2.83 


Fig.    2. — Vigorous   leafy   growth    of   horse    beans    in    citrus    grove    between 
Orange  and  Anaheim,  Orange  County.     Photo  taken  December  30,  1922. 


Horse  beans  are  used  quite  extensively  as  a  cover  crop  in  some 
counties  in  southern  California  at  the  present  time.  (See  figs.  1  and 
2.)  The  type  of  large-seeded  horse  bean  known  as  Windsor  has  been 
grown  in  California  for  a  long  time.  The  green  pods  are  frequently 
seen  in  vegetable  markets,  and  the  seeds  are  shelled  from  the  pods 
and  eaten  in  much  the  same  way  as  green  peas.  The  plants  are  fed 
green  to  cattle  and  the  dry  seeds  used  as  concentrates  by  dairymen. 
Surplus  seed  not  utilized  locally  is  shipped  to  the  large  eastern  cities 
where  it  is  used  in  the  foreign  settlements  as  human  food.    This  last 


i  Woll,  F.  W.,  Productive  Feeding  of  Farm  Animals,  ed.  2,  p.  363. 
2  Harz,  C.  D.,  Landwirthschaftliche  Samenkunde,  p.  664. 


Circular   257]  THE   SMALL-SEEDED  HORSE  BEAN  5 

use  was  at  one  time  quite  important,  but  because  of  the  large  percent- 
age of  bean  weevil,  Bruchus  rufimana,  in  the  seed  shipping  out  of  the 
state  was  considerably  curtailed  by  the  rulings  of  the  Food  and  Drugs 
Act.  The  present  ruling  with  regard  to  interstate  shipment  of  horse 
beans  is  as  follows: 

"151.  Horse  beans:3  The  bureau  will  regard  as  adulterated 
interstate  shipments  of  horse  beans,  otherwise  known  as  broad 
beans  (Vicia  faba),  representing  the  field  run,  which  contain  more 
than  15  per  cent  of  wormy  or  weevil-infested  beans.  The  de- 
liberate addition  to  or  mixture  with  sound  horse  beans  of  wormy 
or  weevil-infested  beans  in  any  amount  will  be  looked  upon  as  a 
violation  of  the  Food  and  Drugs  Act.  The  limit  of  15  per  cent 
should  be  regarded  as  tentative  only  and  may  be  made  more  strin- 
gent in  case  further  investigations  warrant. ' ' 

Horse  beans  may  be  shipped  within  the  State  of  California  for 
cover  crop  purposes,  provided  they  bear  a  certificate  from  the  county 
horticultural  commissioner  that  they  have  been  properly  fumigated. 
The  weevil  does  not  materially  affect  the  use  of  the  seed  as  a  cover 
crop  within  the  state.  If  the  seed  is  placed  in  a  well  sealed  building 
soon  after  it  is  harvested  and  fumigated  for  forty-eight  hours  with 
carbon-bisulfid,  using  2  to  3  pounds  to  100  cubic  feet  of  space,  the 
larvae  will  be  killed  within  the  seed  and  will  not  emerge.  Results  of 
experiments  by  DeOng  show  that  it  is  possible  to  kill  the  broad  bean 
weevil  if  it  is  exposed  for  five  hours  to  a  temperature  of  125°  F. 
Shorter  exposures  are  feasible  at  temperatures  of  140°  to  170°  F.,  but 
this  procedure  is  attended  with  greater  danger  to  germination.  This 
weevil  is  less  susceptible  to  heat  than  is  the  common  bean  weevil, 
Mylabris  {Bruchus)  obtectus,  and  for  that  reason  control  by  fumiga- 
tion is  commonly  recommended. 

Aphids  or  plant-lice  sometimes  seriously  injure  the  young  plant, 
especially  if  planting  has  been  delayed  so  as  to  cause  a  vigorous 
growth  during  warm  weather.  The  remedy  is  to  spray  the  effected 
parts  with  a  tobacco  insecticide  such  as  black  leaf  40  (Nicotine  sul- 
fate) at  the  rate  of  1%  teaspoonfuls  to  one  gallon  of  water  or  with 
1  pound  of  tobacco  leaves  or  stems  steeped  in  four  gallons  of  water. 


3  Bureau  of  Food  and  Drugs.     California  State  Board  of  Health,  p.  53,  Sept. 
1916. 


UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 


DESCRIPTION  OF  THE  HORSE  BEAN  PLANT 

The  horse  bean  plant  is  an  annual  legume  belonging  to  the  vetch 
group,  with  erect  coarse  stems  and  large  leaves  without  climbing 
tendrils.  The  leaves,  consisting  of  from  one  to  three  pairs  of  large 
oval  leaflets,   (see  fig.  3),  are  distributed  from  the  base  to  the  tips 


Fig.  3. — Horse  beans  have  large  leaves  and  succulent  stems.     This  plant  is 
only  three  weeks  old. 


Circular  257] 


THE    SMALL-SEEDED   HORSE   BEAN 


of  the  stems.  The  white  or  purplish  flowers,  with  their  spots  verging 
on  black,  are  borne  in  clusters  on  short  stalks  in  the  axils  of  the 
leaves.  In  the  small-seeded  types  from  two  to  five  pods  develop  from 
a  cluster  of  flowers,  while  the  large-seeded  types  bear  only  one  or  two 


Fig.  4. — A  typical  root  of 
horse  bean  with  its  many 
lateral  branches.  The  strong 
central  tap  root  on  decaying 
leaves  channels  of  humus  in 
the    soil. 


Fig.  5.— The  small- 
seeded  horse  bean  has 
an  unusually  large 
number  of  pods  per 
plant.  This  single 
stalk  has  64  pods. 


pods  in  each  place.  There  is  usually  one  strong  central  root  (see  fig. 
4),  with  numerous  spreading  lateral  rootlets.  These  may  or  may  not 
be  covered  with  nodules,  according  to  whether  there  are  suitable 
bacteria  in  the  soil  or  not.     The  size  of  the  plant  varies  very  con- 


8 


UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 


siderably  according  to  the  variety,  climate,  soil,  rate  of  seeding  and 
methods  of  culture.  A  growth  of  three  feet  may  be  expected  on 
average  orchard  soils,  and  seven  or  more  feet  under  favorable  soil, 
moisture,  and  temperature  conditions.     The  large  number  of  tender 


^^S^^^ 

vx^^^9ka 

\ 

I W- 'ASM*  4 

Fig.  6. — Horse  bean  roots  are  well  supplied  with   numerous  large  nodules. 
(Enlarged.) 


Circular   257]  THE   SMALL-SEEDED  HORSE   BEAN  9 

leafy  stalks  to  a  plant  and  the  taller  growth  greatly  favor  the  small- 
seeded  horse  bean  for  green  manure  purposes.  There  are  about  sixty 
pods  (see  fig.  5),  to  a  stalk  on  the  small-seeded  type,  and  only  about 
fifteen  pods  to  a  stalk  on  the  large  type.  The  average  number  of 
seeds  in  a  pod  is  about  the  same  for  both  types,  viz.,  three  or  four. 
The  seed  of  the  small  horse  bean  is  oval  or  nearly  round  and  about 
one-fourth  to  three-eighths  of  an  inch  long,  while  that  of  the  large 
horse  bean  is  more  or  less  strongly  flattened  and  about  one  inch  long. 
Great  variation  in  size  exists  among  the  different  strains,  grading 
from  very  large  seeds  to  very  small  ones.  (See  pi.  1.)  A  similar  con- 
dition obtains  with  regard  to  the  color  of  the  seeds,  which  ranges 
from  black  to  purple  and  green  with  various  shades  of  brown  pre- 
dominating, in  both  the  large  and  small-seeded  types.  The  weight  of 
the  commercial  small-seeded  Bell  horse  bean,  No.  37,  (see  table  1  and 
pi.  1),  is  sixty-four  pounds  to  a  bushel,  and  that  of  the  commercial 
large-seeded  horse  bean,  No.  3,  fifty-two  pounds  to  a  bushel.  The 
Bell  bean  is  uniform  in  size  and  can  be  seeded  with  a  bean  planter, 
while  the  large  commercial  horse  bean  varies  very  considerably  in  size, 
so  that  the  seeds  may  be  broken  or  the  planter  gets  clogged.  Because 
of  this  difficulty  the  large-seeded  horse  beans  are  usually  sown  broad- 
cast. This  type  of  sowing  entails  the  use  of  a  larger  amount  of  seed 
than  when  a  planter  is  employed  and  usually  results  in  the  seeding 
of  from  one-third  to  one-half  of  the  desired  amount  of  ground  only. 
The  orchardists  commonly  sow  about  ninety  pounds  to  the  acre,  but 
they  would  prefer  to  sow  125  pounds  if  the  cost  were  not  so  great. 


INOCULATION  OF  THE  SOIL 

To  obtain  the  full  benefit  from  a  legume  it  should  have  on  its 
roots  nodules  (see  fig.  6)  that  contain  the  bacteria  which  enable  the 
plant  to  use  the  free  nitrogen  of  the  air.  Without  these  nodules  the 
legume  will  take  most  of  the  nitrogen  for  its  growth  from  the  soil, 
thus  depleting  rather  than  replenishing  or  increasing  its  nitrogen 
content. 

The  horse  bean  belongs  to  the  vetch  group4  so  that  in  most  in- 
stances it  will  be  found  that  the  bacteria  it  requires  are  in  the  soil. 
Should  there  be  any  doubt,  however,  the  soil  or  seed  should  be  inocu- 
lated. One  method  is  to  obtain  soil  from  a  field  that  has  recently 
grown  horse  bean  plants  known  to  have  had  nodules  on  their  roots. 

*  Kennedy,  P.  B.,  Legumes  as  Organic  Fertilizers  in  California  Agriculture. 
Univ.  of  Cal.,  Agri.  Exp.  Sta.  Circular  255,  1922. 


10  UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 

This  soil  is  sprinkled  over  the  land  at  the  rate  of  about  200  pounds 
an  acre  and  immediately  harrowed  in,  or  it  may  be  mixed  with  several 
times  its  weight  of  soil  taken  directly  from  the  field  to  be  planted 
and  drilled  in. 

Another  method  is  the  soil  suspension  method.  It  consists  in 
placing  the  soil  containing  the  proper  bacteria  in  a  tub  or  barrel  and 
mixing  it  thoroughly  with  two  to  three  times  its  volume  of  water. 
The  mixture  should  be  agitated  vigorously  with  a  shovel  several  times 
a  day  for  one  or  two  days.  After  that  the  soil  should  be  allowed  to 
settle  and  the  liquid,  which  will  contain  the  organisms  poured  or 
dipped  off.  The  seed  as  it  is  contained  in  sacks  should  be  dipped  in 
this  liquid  for  a  sufficient  length  of  time,  say  about  ten  minutes,  or 
it  may  be  sprinkled  with  the  liquid,  after  which  it  should  be  spread 
out  to  dry,  preferably  in  the  shade.  Where  the  soil  to  be  used  has 
to  be  shipped  this  method  is  easy,  effective,  and  less  costly.  A  third 
method  of  inoculation  is  to  use  one  of  the  many  commercial  products 
for  the  inoculation  of  legumes.  On  making  application  for  the  bacteria 
the  kind  of  crop  to  be  seeded  should  be  stated.  Full  directions  accom- 
pany the  material. 


CULTURE  OF  THE  HORSE  BEAN 

Horse  beans  are  not  exacting  in  regard  to  the  type  of  soil  they 
require,  but  they  do  best  on  well-drained  heavy  silt  or  clay  loams. 
They  will  also  do  fairly  well  on  sandy  soils,  provided  there  is  ample 
moisture.  Seed  several  years  old  germinates  as  well  as  new  seed, 
so  that  there  is  no  necessity  for  increasing  the  rate  of  seeding  if  old 
seed  is  used.  The  time  to  sow  the  seed  for  cover  crop  purposes  under 
irrigation  is  September,  October,  or  November,  the  exact  preference, 
among  the  three  months,  if  there  is  any,  not  having  been  fully  demon- 
strated. In  localities  with  severe  winters  of  ice  and  snow,  spring  plant- 
ing must  be  practiced.  The  plant  flourishes  in  cool  frostless  weather 
(fig.  7),  and  dislikes  the  summer  heat  of  our  interior  valleys.  Under 
the  latter  circumstances  it  is  also  more  subject  to  fungus  and  insect  at- 
tacks. Seeding  may  be  done  by  machine  or  by  hand.  An  ordinary 
field  bean  planter  may  be  used  for  the  small  horse  bean,  and  a  lima 
bean  planter  for  the  large  horse  bean.  A  corn  or  sorghum  planter 
may  also  be  used  by  providing  a  special  plate  when  it  is  used  for 
beans  or  by  filing  the  grooves  or  holes  to  suit  the  size  of  the  seed.  The 
rate  of  seeding  varies  from  195  pounds  for  the  large  commercial  horse 
bean  (see  No.  3,  table  1  and  pi.  1),  to  79  pounds  for  the  small  commer- 


Circular  257] 


THE    SMALL-SEEDED   HORSE   BEAN 


11 


cial  horse  bean  (see  No.  37,  table  1  and  pi.  1).  This  computation  is 
made  on  the  basis  of  one  plant  for  every  square  foot  when  the  bean  is 
used  as  a  green  manure.  For  beans  used  in  seed  production,  where 
cultivation  is  necessary,  the  rows  should  be  3  feet  apart  and  the  seeds 
placed  from  8  inches  to  1  foot  apart  in  the  row.  (See  fig.  8.)  For 
beans  used  for  green  manure  purposes  on  land  under  irrigation 
cultivation  is  not  necessary,  but  if  the  land  is  so  badly  infested  with 
weeds  that  they  would  choke  the  young  horse  bean  plants,  cultivation 


Fig.  7.  — Small-seeded  horse  bean  plantings  flourishing  in  the  cool  coast  climate 
of  San  Gregorio,  San  Mateo  County,  California. 


12  UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 

should  be  given  them  during  the  early  stages  of  their  growth.  Under 
conditions  where  there  is  not  an  ample  supply  of  water  for  irrigation, 
care  should  be  taken  to  plow  under  the  green  material  at  an  early 
date  so  as  to  allow  for  plenty  of  moisture  in  the  soil  to  aid  in  the 
decomposition  of  the  green  manure.  The  plowing  should  be  done 
early,  even  if  the  green  manure  crop  has  not  attained  the  desired 
height,  as  permitting  it  to  grow  and  further  rob  the  soil  of  moisture 
will  have  a  detrimental  effect  both  on  the  soil  and  the  crop  being 
grown,  or  to  be  grown,  on  the  land.     This  precaution  is  especially 


Fig.  8. — A  dense  stand  is  produced  for  seed  purposes  by  sowing  in  rows  3 
feet  apart. 

necessary  where   the  green   manure   crop   is  being   grown  with  the 
natural  precipitation  as  the  only  moisture  supply. 

If  the  crop  is  being  grown  for  its  seed  care  must  be  exercised  or  a 
large  amount  of  seed  will  be  lost  through  shattering.  The  seed  crop 
may  be  cut  by  hand,  with  an  ordinary  mower,  or  with  a  drop-rake 
reaper.  The  field  should  be  cut  when  the  lower  pods  are  fully  mature 
and  the  upper  ones  well  developed,  but  not  yet  ripe.  A  cloudy  day  or 
early  morning  while  the  plants  are  still  moist  should  be  selected  for 
mowing.  Shocking  may  be  done  by  hand  the  same  day.  (See  fig.  9.) 
When  the  crop  is  sufficiently  dry,  the  small-seeded  horse  bean  may  be 
threshed  with  an  ordinary  bean  thresher  without  difficulty,  a  process 
which  usually  requires  several  days  of  bright  weather.  The  large- 
seeded  types  are  more  difficult  to  thresh  with  a  machine,  the  rolling 
process  being  found  more  satisfactory.  A  yield  of  from  one  to  two 
tons  of  cleaned  seed  an  acre  may  be  expected. 


m 


a 


ikjii 


3 


? 


m 

- 


ITS 


o 


-I 


S3 


- pg 


Plato  1. — Variation  in  sizes  of  d 


I 


•    + 


*  9 


o*  rs« 


© 


O 


' 


:" 


^ 


: 


brent  types  of  horse  bean  seed. 


Circular  257] 


THE    SMALL-SEEDED   HORSE   BEAN 


13 


WORK  OF  THE  CALIFORNIA  AGRICULTURAL 
EXPERIMENT   STATION 

As  early  as  1903,  Stubenrauch  reported  test  plot  experiments  with 
horse  beans  to  be  used  for  green  manuring  purposes.  Of  the  8  varie- 
ties tested  at  the  Amador  Foothill  substation  at  Jackson,  only  2 
proved  to  be  too  tender  to  warrant  further  trials.  The  lowest  tempera- 
ture recorded  was  21°  F,  which  occurred  in  February.  Only  2 
of  the  varieties  tested  proved  to  be  sufficiently  frost  resistant  to  serve 


Fig.  9. — The  windrows  of  horse  beans  are  being  placed  in  bunches  to  prevent 
excessive  shattering. 

for  winter  growth  in  the  foothills.  The  estimated  yield  of  green  stuff 
to  the  acre  was  11,003  pounds  for  No.  7943,  and  9,755  pounds  for  No. 
7035.  At  the  San  Joaquin  Valley  substation  near  Tulare,  which  is 
located  on  land  containing  more  or  less  alkali,  in  the  case  of  experi- 
ments made  during  an  exceptionally  cold  winter,  the  horse  beans 
were  disappointing  and  produced  comparatively  low  yields.  The 
plots  were  all  irrigated,  but  were  sown  too  late.  The  two  best  varieties 
were  No.  1453  which  produced  7,481  pounds  and  No.  1454  which 
produced  8,348  pounds  to  the  acre.  At  the  Southern  California  sub- 
station at  Chino,  San  Bernardino  County,  the  horse  beans  were  the 
most  promising  green  manure  plants  tested,  making  a  rapid  winter 
growth.    No.  7943  produced  the  highest  yield,  with  44,528  pounds  of 


14  UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 

green  stuff  to  the  acre.  These  estimates  were  calculated  from  weigh- 
ings of  the  growth  on  one  or  two  square  yards,  and  may  perhaps  be 
considered  maxima  in  all  cases.  The  heavy  succulent  root  growth 
was  particularly  noticeable,  and  it  assisted  greatly  in  opening  up  the 
soil  and  adding  materially  to  the  humus.  At  the  central  station  at 
Berkeley  sixteen  varieties  were  planted.  The  experiments  there 
demonstrated  that  horse  beans  require  from  about  ten  to  fourteen  days 
to  germinate,  the  length  of  time  being  dependent  upon  the  season 
when  they  are  grown.  The  date  of  planting  was  October  28,  and  the 
green  stuff  was  plowed  under  about  the  end  of  March.  The  test  plots 
demonstrated  that  the  horse  bean  was  one  of  the  most  promising  of 
winter-growing  legumes  for  green  manure  purposes,  giving  the  highest 
yield  of  green  stuff  on  record.  The  estimated  yields  of  green  stuff 
calculated  from  small  weighings  were  as  follows: 

No.  1454,  68,970  pounds  to  the  acre. 

121 
No.    -T^r  58,624  pounds  to  the  acre. 

No.  7942,  55,750  pounds  to  the  acre. 
No.  1453,  51,727  pounds  to  the  acre. 


EXPERIMENTS  MADE  AT  THE  UNIVERSITY  FARM 

AT  DAVIS 

Plantings  of  23  varieties  were  made  at  Davis  in  the  fall  of  1916 
and  31  in  the  fall  of  1917.  Most  of  the  seed  for  these  test  plots  was 
secured  from  the  office  of  Grass  and  Forage  Plant  Investigations  of 
the  United  States  Department  of  Agriculture.  They  were  grown 
without  irrigation  and  planted  in  December  11  and  12,  1916,  and 
December  22,  1917.  The  growth  of  the  different  varieties  when  they 
were  in  blossom,  about  May  1,  ranged  from  18  to  36  inches.  This  is  a 
small  growth  and  indicates  that  Davis  is  not  very  well  suited  to  the 
growing  of  horse  beans  without  autumn  irrigation.  The  beans  were 
found  to  be  especially  resistant  to  frost  injury.  The  leaves,  although 
frosted  at  night,  would  recover  during  the  day.  There  were  from  10 
to  24  pods  on  each  plant,  with  an  average  of  3  seeds  in  a  pod.  The 
lowest  yield  of  seed  to  an  acre  was  estimated  to  be  1150  pounds  and 
the  highest  1830  pounds.  No  weights  were  taken  to  estimate  tonnage 
for  green  manure.  The  growth  and  yields  obtained  at  Davis  are  very 
much  less  than  those  obtained  on  the  coast,  where  there  is  more  rain- 
fall and  the  winter  conditions  are  less  severe. 


Circular  257] 


THE    SMALL-SEEDED   HORSE   BEAN 


15 


INFLUENCE  OF  THE  WEIGHT  OF  SEED  ON  THE  RATE  OF 

SEEDING 

The  chief  drawback  to  the  extensive  use  of  horse  beans  as  a  winter 
cover  crop  has  been  the  large  size  of  the  seed  ordinarily  obtainable  on 
the  market,  which  makes  the  rate  of  seeding  prohibitive.  Table  1  shows 


Fig.  10. — Height  of  small-seeded  horse  beans  at  the  time  of  harvesting  for 
seed. 

that  the  largest  seed,  No.  1,  weighs  3.13  grams.  A  pound,  therefore, 
would  contain  145  seeds,  and  the  rate  of  seeding  necessary  in  this 
case  would  be  300  pounds  to  the  acre.  This  calculation  is  based  on  a 
rate  that  would  allow  one  plant  to  every  square  foot  of  ground,  or 


16  UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 

what  we  would  consider  an  ideal  spacing  for  a  cover  crop.  The  method 
of  seeding  proposed  is  to  plant  the  beans  in  two-foot  rows  with  the 
seeds  placed  6  inches  apart  in  the  row,  or  if  it  is  more  convenient 
they  might  be  sown  in  rows  1  foot  apart  with  the  seed  12  inches  apart 
in  the  row.  It  has  been  proved  in  our  test  plots  that  the  size  of  the 
seed  does  not  influence  the  size  of  the  plants,  the  smaller  seeds  having 
a  tendency  to  produce  plants  with  a  greater  number  of  stems.  No.  64, 
table  1,  the  smallest  of  the  seeds,  weighs  only  0.12  gram  and  gives 
3775  seeds  to  the  pound,  so  that  only  11%  pounds  of  seed  an  acre 
would  be  required.  Our  experiments  are  being  conducted  with  a 
view  to  selecting  No.  64  so  as  to  introduce  it  into  the  seed  trade.  The 
cost  by  the  acre  to  the  fruit  grower  would  then  be  very  considerably 
reduced.  Taking  the  commercial  horse  bean  as  No.  3  (pi.  1,  table  1) 
with  223  seeds  to  the  pound  and  a  requirement  of  195  pounds  to  the 
acre,  the  cost  at  4  cents  a  pound  would  be  $7.80  an  acre,  while  No.  64 
(pi.  1  table  1)  at  ll1/^  pounds  an  acre  and  10  cents  a  pound  would 
cost  $1.15  per  acre,  or  if  the  beans  could  be  raised  for  4  cents  a  pound, 
the  cost  would  be  46  cents  an  acre.  Comparing  the  small-seeded  horse 
bean  with  vetch  at  6  cents  a  pound,  with  a  requirement  of  70  pounds 
of  seed  an  acre,  the  cost  would  be  $4.20  an  acre. 

To  all  appearances  there  is  a  discrepancy  in  plate  1,  a  seed  which  is 
apparently  smaller  in  some  cases  preceding  a  larger  one.  The  table 
and  illustration,  however,  are  based  on  the  weight  of  the  seeds,  so  that 
while  No.  30  appears  larger  than  No.  29,  by  actual  weight  it  is  less. 

Table  1. — Influence  of  weight  of  seed  on  rate  of  seeding: 


Wt.  of  1  seed 

No.  of  seeds 

*Lbs.  required 

Number 

in  gms. 

per  lb. 

per  acre 

1 

3.13 

145 

300 

2 

2.37 

191 

228 

3 

2.03 

223 

195 

4 

1.97 

230 

189 

5 

1.91 

237 

183 

6 

1.82 

243 

179 

7 

1.78 

254 

171 

8 

1.66 

273 

160 

9 

1.64 

276 

157 

10 

1.64 

276 

157 

11 

1.63 

278 

155 

12 

1.61 

281 

154 

13 

1.58 

287 

152 

14 

1.49 

304 

143 

15 

1.49 

304 

143 

16 

1.39 

326 

133 

]7 

1.38 

328 

132 

*  Seeding  rate  figured  on  cover  crop  basis  with  one  plant  per  square   foot 
on  area  actually  sown  to  cover  crop. 


Circular  257] 

THE  SMALL-SEEDED 

HORSE  BEAN 

Wt.  of  1  seed          No.  of  seeds 

*Lbs.  required 

Number 

in  gms. 

per  lb. 

per  acre 

18 

1.37 

331 

131 

19 

1.27 

351 

122 

20 

1.22 

371 

117 

21 

1.20 

377 

115 

22 

1.15 

394 

110 

23 

1.14 

397 

109 

24 

1.12 

404 

107 

25 

1.06 

427 

102 

26 

1.03 

440 

99 

27 

1.02 

444 

98 

28 

1.01 

448 

97 

29 

.97 

467 

93 

30 

.93 

487 

89 

31 

.92 

492 

88 

32 

.91 

498 

87 

33 

.88 

515 

84 

34 

.87 

520 

84 

35 

.87 

520 

84 

36 

.85 

533 

82 

37  (Bell)  ( 

.82 

552 

79 

38 

.81 

560 

78 

39 

.79 

573 

76 

40 

.75 

604 

72 

41 

.73 

620 

70 

42 

.69 

656 

66 

43 

.60 

755 

57 

44 

.58 

781 

56 

45 

.56 

809 

54 

46 

.53 

855 

51 

47 

.50 

906 

48 

48 

.48 

944 

46 

49 

.46 

985 

44 

50 

.45 

1000 

43 

51 

.43 

1053 

41 

52 

.42 

1078 

40 

53 

.40 

1132 

38 

54 

.38 

1190 

36 

55 

.36 

1258 

34 

56 

.35 

1294 

33 

57 

.34 

1332 

32 

58 

.31 

1461 

30 

59 

.31 

1461 

30 

60 

.25 

1812 

24 

61 

.22 

2060 

21 

62 

.18 

2516 

17 

63 

.17 

2664 

16 

64 

.12 

3775 

11.5 

17 


*  Seeding  rate  figured  on  cover  crop  basis  with   one  plant  per  square  foot 
on  area  actually  sown  to  cover  crop. 


18 


UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 


CO-OPERATIVE  EXPERIMENTS 

A  small-seeded  type  of  horse  bean  has  been  grown  for  home  use 
at  San  Gregorio,  San  Mateo  County,  for  thirty-five  years,  the  seed 
having  been  brought  originally  from  England  by  Jesse  Palmer.  Two 
years  ago  his  grandson,  Frank  P.  Bell,  decided  to  multiply  the  beans 
on  a  field  scale  for  cover  crop  purposes.  (See  fig.  10.)  Up  to  this 
time  the  horse  bean  commonly  grown  in  the  vicinity  had  been  the 
large  flat  Windsor  type.  Mr.  Bell's  plants  were  examined  in  the  field  and 


Fig.  11. — The  small-seeded  horse  bean  attains  a  height  of  more  than 
when  ready  to  cut  for  hay. 


feet 


a  number  of  different  forms,  all  small-seeded  but  varying  very  consider- 
ably in  size  of  seed,  leafage,  number  of  pods  on  the  plant  and  flower 
characters,  were  found.  With  a  view  to  standardizing  some  of  these, 
selections  have  been  made  with  two  main  objectives  in  view — size  of 
seed  and  amount  of  leafage. 

The  field  run  of  the  Bell  type  is  represented  by  No.  37,  table  1, 
plate  1.  These  beans  are  now  being  grown  on  a  commercial  scale  on 
heavy  soil  without  irrigation.  A  Black  Hawk  planter  is  used  for 
seeding  after  filing  the  ridge  off  as  is  shown  in  seed  plate  No.  F348. 
Any  corn  or  bean  planter  could  be  used  by  adjusting  the  seed  plates. 

The  rate  of  seeding  was  25  pounds  an  acre,  the  rows  being  3  feet 
apart  with  the  seed  12  inches  apart  in  the  row,  which  is  a  sufficient 
space  for  seed  purposes  on  good  soil,  but  not  for  a  cover  crop  where 


Circular  257] 


THE    SMALL-SEEDED   HORSE   BEAN 


19 


maximum  leafage  is  desirable.  The  date  of  seeding  was  December  12, 
1921.  The  plants  were  well  up  and  the  rows  showing  by  December 
28.  The  full  blossoming  period  was  about  April  10,  1922.  The  fields 
were  being  cut  for  seed  on  July  20,  and  the  plants  averaged  6  feet  in 
height.  (See  fig.  11.)  Estimates  from  small  weighings  of  plants 
taken  June  26  indicated  20  tons  of  green  stuff  to  the  acre.  Other 
plantings  made  in  February  and  March,  1922  matured  seed  in  August. 


COMPOSITION  OF  THE  GREEN  MATERIAL 

The  following  analysis  (table  2),  were  kindly  furnished  us  by  the 
Division  of  Nutrition.  The  samples  were  gathered  in  the  field  and 
represent  three  stages  in  the  growth  of  the  small  horse  bean. 

Table  2. — Analyses  op  Green  Material,  Small-seeded  Horse  Beans 


Sample 
No. 

Date  of 
Seeding 

Moisture 

per- 
centage 

Protein 

per- 
centage 

Ether 
Extract 

per- 
centage 

Ash 
per- 
centage 

Crude 
Fiber 
per- 
centage 

Nitro- 
gen 

Fr.  Ex. 

per- 
centage 

Condition  of 
Growth,  June  26 

3953* 

Dec.  12, 
1921 

79.43 

3.51 

0.37 

1.10 

4.41 

11.18 

Height  75  inches 
Pods,  no  blossoms 

3952* 

Feb.  12, 

1922 

83.38 

3.55 

0.46 

1.23 

3.72 

7.66 

Height  53-60  inches 
Blossoms  and  pods 

3951* 

March  25, 
1922 

86.59 

3.00 

0.59 

1.34 

3.28 

5.20 

Height  40  inches 
Blossoms,  no  pods 

*  Samples  taken  June  26,  1922. 

The  analyses  show  that  the  percentage  of  moisture  is  greatest  when 
the  plants  are  in  blossom,  decreasing  as  they  reach  maturity.  Figured 
on  a  dry  basis,  the  percentage  of  nitrogen  would  be  2.72  for  No.  3953, 
when  the  plants  were  past  the  blossoming  period;  3.37  for  No.  3952, 
when  the  plants  had  both  blossoms  and  pods;  and  3.58  for  No.  3951, 
when  the  plants  had  a  large  number  of  leaves  and  blossoms  but  no 
pods  had  been  formed. 

The  amount  of  nitrogen  contained  in  100  pounds  of  the  material 
would  be  .56  for  No.  3953,  .57  for  No.  3952,  and  .48  for  No.  3951 ;  or 
approximately  %  pound  of  nitrogen  for  every  100  pounds  of  material 
turned  under.  Estimating  the  yield  of  green  material  as  20  tons  an 
acre,  we  would  be  adding  to  the  soil  approximately  200  pounds  of 
nitrogen  an  acre. 


20 


UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 


These  figures  represent  the  nitrogen  in  the  tops  of  the  plants  only 
and  do  not  include  a  considerable  amount  of  it  which  is  present  in 
the  roots  with  their  nodules.  Sample  No.  3953  from  the  crop  planted 
on  December  12,  1921  was  taken  June  26,  after  the  blossoming  period, 
when  the  plants  were  75  inches  high  with  their  pods  well  filled.  Sample 


Fig.  12. — Horse  beans  and  oats  make  a  palatable  and  nutritious  silage. 

No.  3952  from  the  crop  planted  on  February  12,  1922  was  taken  June 
26  when  the  blossoms  and  pods  were  about  equally  represented  and 
the  plants  were  from  53  to  60  inches  high.  Sample  No.  3951  from  the 
crop  planted  on  March  25,  1922  was  taken  June  26,  when  the  beans 
were  in  blossom  with  no  pods  present  and  the  plants  were  40  inches 
high. 


Circular  257] 


THE   SMALL-SEEDED   HORSE   BEAN 


21 


SILAGE  FROM  THE  SMALL  HORSE  BEAN 

In  order  to  determine  whether  horse  beans  would  make  good  silage, 
some  green  material  grown  at  San  Gregorio  without  irrigation  was 
chopped  up  when  well  podded,  after  the  blossoming  period,  and  mixed 
with  50  per  cent  of  red  oat  hay  in  the  milk  stage  and  pressed  into  a 
barrel.  (See  figs.  12  and  13.)  This  was  done  on  June  26,  1922.  On 
opening  the  barrel  on  November  19  the  contents  were  found  to  be 
moulding  on  top  and  the  side,  owing  to  the  air's  getting  in  at  the 


■3 

a 

^t       \V 

-^s.w5^99hiNh 

- 

\ 

\           A 

' 

H^HBSi^j 

H 

-• 

^T^^M 

Fig.  13. — The  material  is  coarse,  but  analyses  show  that  it  is  very  high  in 
protein. 


cracks  in  the  sugar  barrel.  The  remainder  of  the  material  was  in 
excellent  condition,  however,  moist,  with  all  the  leaves  whole  and  not 
disintegrated.  The  characteristic  silage  odor  was  present.  In  table 
3  below,  the  composition  of  the  small-seeded  horse  bean  and  oat  silage 
is  compared  with  two  of  our  commonly  used  silage  crops,  Indian  corn 
and  sweet  sorghum.  The  analyses  made  there  indicate  that  the  horse 
bean  and  oat  silage  is  higher  in  protein  than  either  Indian  corn  or 
sweet  sorghum.  The  nutrients  may  be  made  more  comparable  by  reduc- 
ing the  material  to  a  dry  basis,  which  would  give  13  per  cent  of  protein 
for  horse  bean  and  oats,  9.9  for  Indian  corn  and  6.6  for  sweet  sorghum. 
The  percentage  of  fat  on  the  same  basis  would  be  4.1,  2.6,  and  2.0 
respectively. 


22 


UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 


Table  3. — Comparison  of  Horse  Bean  and  Oat  Silage  with  Indian  Corn 
Silage  and  Sorghum  Silage 


Moisture 
per- 
centage 

Protein 

per- 
centage 

Fat 
per- 
centage 

Ash 
per- 
centage 

Crude 
Fiber 
per- 
centage 

Nitrogen 
Fr.  Ex. 

per- 
centage 

Acid  percentage 

Sample 

Volatile 

Fixed 

5Small-seeded 
Horse  Bean 

73.00 

3.51 

1.12 

2.07 

6.25 

14.00 

0.38 

1.08 

6Indian  Corn 

73.07 

2.69 

.71 

2.06 

5.72 

15.75 

0.41 

2.09 

7Sweet  Sorghum 

78.27 

1.44 

.45 

1.85 

6.80 

11.20 

0.51 

1.22 

5  Analyses  kindly  made  for  us  by  the  Division  of  Nutrition, 
s,  7  Woll,  F.  W.,  and  Voorhies,  E.  C.     Trials  with  California  silage  crops.    Bull. 
282,  Calif.  Agr.  Exp.  Sta.,  1917,  p.  24. 

The  experiment  demonstrated  that  it  is  quite  feasible  to  make 
silage  of  excellent  quality  from  red  oat  hay  and  horse  beans.  As  the 
inhabitants  of  the  region  involved  are  engaged  to  a  large  extent  in 
dairying  and  this  crop  is  raised  without  irrigation,  the  building  of 
silos  and  the  filling  of  them  with  horse  beans  and  green  oats  for 
silage  would  be  a  practicable  method  of  providing  succulent  material 
throughout  the  year. 

In  this  connection  we  quote  the  following  from  the  Pacific  Rural 
Press  of  December  16,  1916,  "My  experience  is  that  green  horse  bean 
plants  are  beneficial.  Several  years  ago  I  broadcasted  a  mixture  of 
horse  beans  and  barley  in  my  young  orchard.  It  made  a  good  growth, 
and  before  plowing  in  the  spring  I  cut  and  fed  it.  The  cows  cleaned 
it  up  well  and  increased  their  milk.  We  noticed  no  bad  effects  on 
the  milk  or  cream.  I  have  noticed  that  both  the  cows  and  the  hogs 
prefer  the  green  barley  or  alfalfa  to  the  green  horse  beans. 

"The  same  time  I  fed  the  horse  beans  I  put  part  of  it  in  the  silo 
with  a  filling  of  alfalfa,  but  did  not  find  any  difference  when  I  fed  it 
out.  I  believe  that  horse  beans  green  would  make  good  silage.  The 
cured  horse  beans  are  fine  grain  for  dairy  cows.  They  will  increase 
the  milk  flow  and  the  quality  of  the  cream. ' '  W.  J.  Hanna,  Gilroy, 
California. 


Circular  257]  THE  small-SEEDED  HORSE  BEAN  23 


DECOMPOSITION  OF  THE  GREEN  MANURE 

Little  definite  field  knowledge  is  available  with  regard  to  precisely 
what  takes  place  when  organic  matter  is  incorporated  with  the  soil. 
In  loose  warm  moist  soils  quantities  of  available  nutrients  may  be 
produced  in  from  two  to  four  weeks,  the  maximum  amount  occurring 
in  from  four  to  twelve  weeks.  Martin8  concludes  from  his  experiments 
that  the  more  succulent  the  green  manure  the  more  readily  it  decays 
and  therefore  the  more  quickly  the  nutrients  are  available.  If  the 
green  material  is  incorporated  with  the  soil  at  a  half  mature  stage, 
it  produces  the  largest  yields  of  subsequent  crops.  He  recognizes 
three  periods  in  connection  with  the  breaking  down  of  the  organic 
matter : 

1.  The  accumulation  of  humus  in  the  soil. 

2.  The   decomposition   of   the   humus   and   the   production   of 

nitrates. 

3.  The  rapid  decrease  of  the  humus. 


SUGGESTIONS 

The  small-seeded  horse  bean  should  be  grown  as  a  winter  green 
manure  crop  in  the  orchards  of  the  Santa  Clara  Valley  and  similar 
sections,  in  the  grape  and  citrus  sections  of  southern  California,  and 
in  all  parts  of  the  state  which  have  a  moderate  winter  climate.  In 
the  coastal  regions  which  are  not  adapted  to  the  standard  silage  crops, 
Indian  corn  or  sorghum,  the  small-seeded  horse  bean  should  find  a 
valuable  place  in  the  cropping  system  of  those  engaged  in  the  dairy 
industry.  Truck  gardeners  in  the  coastal  sections,  in  the  Imperial 
Valley,  and  in  other  sections  of  the  state  near  the  cities,  are  finding 
it  more  and  more  difficult  to  obtain  organic  fertilizers.  The  small- 
seeded  horse  bean  may  aid  in  solving  their  difficulty. 

8  Decomposition  of  green  manures  at  different  stages  of  growth.  Bulletin  406, 
Agr.  Exp.  Sta.,  Cornell  University,  Aug.  1921. 


